Expansion bit and reamer



June 11, 1940. J, Q'GRADY 2,203,998

EXPANSION BIT AND REAMER Filed Aug. 15, 1958 2 Sheets-Sheet 1 II" I ll: 1" {L I i A? II YT f zik IN VENTOR DANIEL J. O'GRAJ) y 7 I ATTORNEY Patented June 11, 1940 PATENT OFFICE EXPANSION BIT AND REAMER Daniel J. OGrady, Los Angeles, Calif assignor to 3 H. John Eastman, Long Beach, Calif.

Application August 15,

15 Claims.

My invention relates generally to well drilling tools, and more particularly to a bit, especially designed for drilling through rock and earth formations, and the bit being constructed so that it 5 may be effectively employed for reaming operations in order to increase the size of the well holes above their normal diameters, and which operation is sometimes necessary in order to permit the lowering of the casing or pipe into the well hole. Theprincipal objects of my invention are, to generally improve upon and simplify the construction of the existing forms of expanding bits and reamers; further, to provide a. bit having rotary cutters mounted for limited swinging l5 movement upon the lower portion of the body of the tool, which cutters are expanded or moved outward by fluid pressure on a piston having operating connections with the swinging blocks or jaws that carry the rotary cutters, and said 20 cutters also being expanded and maintained in such expanded conditionby the weight of the drill pipe thatcarries the tool; and further, to provide for circulation of fluid through the tool to faeilitate the drilling and reaming operations, 25 and which circulation discharges from a jet that is directed downwardly from ayflow-beanpositioned between the rotary cutters.

Further objects of my invention are, to provide structure, so as to resist to a maximum degree,

the strains and stresses to which it is subjected while in service; further, to mount the rotary bits on anti-friction bearings, so as to facilitate the 35 operation of said bits; further, to construct the body of the bit and the expanding blocks or legs that carry the rotary cutters, so as to equalize to the greatest possible degree the service strains and stresses that are impressed on the body of m the tool and the cutters"; and further, to arrange between the piston that is actuated by fluid pressure to expand the rotary cutters, and the blocks or legs that carry said cutters, a piston rod and cross-head connection which, when moved downward, swings the cutter-carrying legs or blocks upon their axes," so as to efiect the expanding function of the-bits.

A further object ofmyinvention is to construct an expanding bit and reamerwherein the oper}.

ating parts thereof areprotected to such a degree,

as to minimize the possibility of cuttings or shale from entering the tool, while the same is being Withdrawn from the wellhole with thecutter-y.

carrying leg sor blocks in closed positions. i5 Withtheioregoing and other objects in view,

1938, Serial No. 224,908

my invention consists: in certain novel features of construction and arrangement of parts that will be hereinafter more fully described and claimed and illustrated in the accompanying drawings in which: 5

Fig. 1 is a side elevational view of an expanding rock bit and reamer constructed in accordance with my invention.

Fig. 2 is a vertical section taken on the line 2-2 of Fig. 1. a Fig. 3 is a vertical section, partly in elevation, and taken on the line 3-3 of Fig. 2.

Fig. 4 is a horizontal section taken on the line 4-4 of Fig. 5 and looking in the direction indicated by the arrows on said line. l

.Fig. 5 is a vertical section taken through the lower portion of the tool,and showing the cutters and the plates that carry the same inclosed positions. a a

,Fig. 6 is an elevational View, partly in section of the lower portion of the piston rod and the trun nions carried thereby.

Fig. 7 is a perspective .view of the jet nozzle that is removably positioned in the lower end of the piston rod for producing a restricted fluid pressure outlet.

Referring by numerals to the accompanying drawings which illustrate a preferred embodiment of my invention, It designates the body of the tool which may be substantially cylindrical in shape, with its lower portion slightly increased in diameter, and formed axially through said body is a concentric bore l l, the upper portion of which is threaded as designated by It, in order to receive the threaded lower endof the drill pipe. 35

The enlarged lower portion of the body It is provided with a diametrically arranged slot 12, which intersects the lower end of bore ii, and formed integral with and depending from the lower end of the body 10 between the ends of slot l2 are arms H, the lower portions of which are integrally connected by a short cylindrical block I4, in which is formed a vertically disposed concentric threaded opening I5. r

Screw seated in the threadedopcning i5, is the threaded shankon the upper end of a. convene tional guide IE, or when the. toolis being used as a reamer, member it may be. a drill or bit of any desired form. r i l r r Arranged for sliding movement in the lower portion. of the bore II in the body 50, is a tubular piston rod ll, on the upper end of which is mounted a piston comprising a discshaped body IS, on the top of which is secured a cup leather packing [9.

Removably seated in the lower end of the bore through piston rod ll, is a jet nozzle or flow-bean 26 which is for the purpose of directing a jet of fiuid downwardly into and through the space between the depending arms l3 and the length of the space between said arms is such that the force of the jetof fluid is dissipatedto such an extent as it passes through the space between said arms, that it does not affect or cut the metal in the lower portion of said arms and the block it that connects the lower ends'thereof. This flow-bean also functions to control the reactive pressure of the fluid on top of the piston carried by the upper end of piston rod l'l. Flow-bean 26 is screw seated in the lower portion of the piston rod, in order that it may be conveniently interchanged with flow-beans having larger or smaller bores, thus regulating the size of the jet delivered downwardly between the arms l3 and controlling the degree of reactive pressureon the piston.

The upper end of the bore through the flowbean is countersunk, and suitably secured on the countersunk surface is a facing 2! of wear resisting metal.

Projecting from the. lower end of piston rod I1, are diametrically opposite trunnions 22 that constitute a crosshead, and mounted on said trunnions are bushings 23 of wear resisting metal.

The other ends of this crosshead traverse vertically disposed guide grooves 23a that are machined in the opposite side faces of the transverse slot or opening I2 (see Figs. 3 and 4:)

Seated in the walls of the body member it, to the sides of opening l2, and disposed equi-distant on opposite sides of the axis of the tool and the piston rod l1, are horizontally disposed pins 24 that constitute axes for the plates that carry the rotary cutters, and these pins are secured in position by means of set screws 25 that are seatedin the body Ill just above the transverse slot [2, and the inner ends of which said screws engage said pins (see Fig. 1).

Mounted for swinging movement upon pins 24;, are the plates 26 of metal that function as carriers for the rotary cutters. The upper ends of the plates 26 conform to the shape of the upper surfaces of the ends of the transverse slot or opening I2, and when the plates 26 are expanded, or swung outward to their limits of movement, the upper I of the tool. At the inner ends of the surfaces I2a,

the opening i2 is provided with inclined surfaces l2b Which function as shoulders or stops against which the upper edges of the plates 26 engage when swung inwardly to their limit of movement, as illustrated in Fig. 5.

The lower portions of the rotary cutter carrying plates 26 project a short distance below the lower end of body lll, and when said plates are swung inwardly toward each other to their limits of movement, as illustrated in Fig. 5, the inner lower portions of said plates occupy positions within the opening between the arms [3 with the inner lower faces of said plates in direct contact with each other.. (See Fig. 5.)

When so positioned, the outer faces of the plates 26 are practically flush with the outer face of the enlarged lower portion of body If).

Portions of the plates 26 immediately below their upper inner corners are cut away to form 2,203,998 I e 1 a v substantially semi-circular notches 29, for the accommodation of the trunnions 22 and the bushings 23 carried thereby, and the size of these notches is practically the same as the diameters of the bushings, so that when the cutter carrying plates are expanded as illustrated in Fig. 2, the bushed trunnions fit snugly in said notches.

The inner faces of the upper portions of the plates 26 above the notches 29are slightly inclined to form shoulders 36 that are spaced apart when the plates 26 are moved inward to their limits of movement, and which shoulders make direct contact with each other, when the plates are expanded as illustrated in Fig 2. j

v The upper inner portions of the legs 26 above the notches 29 and between the shoulders 39 are cut away to provide vertically disposed notches 30a, that are semi-circular in horizontal section,

for the accommodation of that portion of the piston rod ll directly above. the crosshead, thus enhancing the desirable result of maintaining the cutter carrying legs in a central position within the tool body.

Thus when the cutter carrying plates 26 are expanded to their limits as illustrated in Fig. 2,

the tops of said plates 26 have direct bearing against the stop surfaces l2a at the ends of the slot or opening l2, and the shoulders 36 have direct engagement with each other, and thus the expanding movement of the plates is effectively limited.

The lower outer portion of each plate 26 is cut away to form. a pocket or recess 3|, for the accommodation of a rotary cutter 32, the latter being provided on its periphery with teeth 33, and each cutter is mounted for rotation on the shank of a bolt 34, the outer end thereof being provided with a head 35. Formed in the outer face of head is a pair of recesses 36 adapted to receive a spanner wrench or like tool, that is utilized in seating and unseating the threaded inner portion 31 of the bolt into the inner lower portion of the arm or leg 26.

Anti-friction bearings 38, either spherical or cylindrical, are arranged between each rotary cutter 32 and the bolt on which it is mounted.

After the bolt 34 and rotary cutter have been properly applied to the plate 26, a plug 39 is positioned directly over the outer face of the rotary cutter around the head 35 of .bolt 34, and the upper and side edges of this plug are welded to the outer face of the plate 26. Thus the plug 39 provides a solid and practically integral wall that closes the outer portion of the pocket or recess 3|, and said plug also furnishes protection for the outer face of the rotary cutter. f

The inner faces of the plates 26 below the. notches 29 are provided with vertically disposed grooves 40 for the accommodation of the flowbean 20 and the jet that issues therefrom when the cutter carrying plates are closed (see Fig. 5).

The outer face of each plug lies flush with theouter face of the plate in which it is seated.

In the operation of my improved bit and reamer, the body l0 and parts carried thereby are rotated as the drill pipe to whichthe body is connected is rotated, and in order to expand the plates 26 that carry the rotary cutters, fluid under pressure is pumped downwardly through the drill pipe, with the result that pressure is exerted upon the piston l8, thereby moving piston rod If and the trunnions 22 downward, which action engages the lower portions of the surfaces of the notches 29, and swings the cutter carrying When-swung outward totheir limits of move-v ment, the platesand rotary cutters carried thereby occupy the positiens as illustrated in Fig. 2, it ,with the upper ends of the plates bearing against the upper portions of the surfaces of the transverse slot or opening I 2, and with the shoulders 30 bearing directly against each other.

When so positionedfthe lower portions of the the well hole is reamed and consequently incutters 32 project a substantial distance beyond. the surface of the body l0, so that in operation creased in diameter.

During operation a jet of fluid under pressure discharges downwardlyfrom flow-bean 20 into;

i the space between arms 13, thus providing ample fiuidto bring about circulation of the cuttings removed by the tool and as the opening between the arms I3 is of considerable length, the force of this jet of fluid will be dissipated as it,passes downwardly and consequently said jet will not tend to cut out or afiect the lower portions of the, arms I3 and block l4.

,In this connection it willbe understood that acirculation of fluid is essential inthe drilling and reaming operations.

Inasmuch as the opening through flow-bean 20 is considerably smaller than the diameter of the opening II, a certain degree of reactive pressure will be developed in the flow passing through the tubular piston l1, and such reactive prester line that is at an angle relative to the vertical or the axis of the body of the bit, andfrom this center line the cutter carrying plates are further expanded and maintained in such expanded condition by the weight of the drill pipe, to which the, tool is connected.

As hereinbefore stated, the expansion or out- Ward swinging movement of the cutter carrying plates 26 is limited by the engagement of the upperend of said plates against the tool body, r ;and the engagement of the shoulders 30 against each other.

This expansion or outward movement of the cutter carrying plates may be varied and controlled bychangin the angle on the upper ends of the plates. In the construction here:

in illustrated, the upper ends of the plates are inclined with respectto the vertical or axis of the tool when the plates are closed,.and when said legs are expanded, theupper ends thereof occupy a plane at right angles totheaxis of the 3 tool.

The cutters, when fully expanded and reaming or drilling in a well bore, are cutting at an angle relative to the vertical, and the upward thrust on each cutter carrying plate, is at an angle corresponding to the angle the cutter is presenting to the vertical of the well bore. This angular thrust on :the cutter carrying plates tends to maintain the cutters in expanded positions; also suclrangular upward thrust against the right angle seats, forces the cutter platesinto the center line of the body, thereby equalizing said force, and the latter is controlled by the fulcrum pins 24, the crosshead comprising the trunnions 22, and the ends of which trunnions traverse the guide slots 230, that are formed within the lower portion of the body l0. Further, the piston rod and piston are, during all operations, in direct alignment with the bore II and the axis of the body 10, and which alignment is preserved by the engagement of the ends of the crosshead on the lower end of the piston rod in the guide slots 23a. i

The flow-bean 20 is made removable from the lower end of the tubular piston rod, in order that it may be conveniently removed and replaced in the event that the continued flow of circulation through the bean cuts the same, so as to render it unfit for service. i

- The upper portions of the plates 26 engage around the lower portion of the piston rod and the crosshead, so as to materially assist in maintaining] said plates centrally within the lower portion of the tool body.

The heads of the pins 34 on which the rotary cutters are mounted may be welded to the blocks 39, thus providing positive means for preventing the pins from becoming loose and dropping out while the tool is inthe well hole.

The construction of the tool, and particularly the cutter carrying plates, is such as to efiectively minimize the possibility for cutting slivers 'or shale that might enter the tool to render the same ineffective in operation, and this protection is particularly effective while the cutter carrying plates are closed and the tool is being drawn from the well.

Thus it will be seen that I have provided an expanding rock bit and reamer that is relatively simple in construction, inexpensive of manufacture, and very effective in performing the functions for which it is intended.

, Itwill be understood that minor changes in the size, form, and construction of the various parts of my improved rock bit and reamer, may be made and substituted for those herein shown and described, without departing from the spirit of my invention, the scope of which is set forth in the appended claims.

I claim as my invention: 1. In an expansion bit and reamer, a tubular body adapted to be detachably connected to a drill pipe, a pair of plates pivotally mounted in the lower portion of said body and adapted to swing outwardly therefrom, apiston arranged for reciprocatory movement within said tubular body, a piston rod depending from said'piston, a crosshead on the lower portion of said piston rod, the upper inner corners of which plates are recessed vertically and transversely for said crosshead and the lowerportion of said piston rod.

2. In an expansion bit and reamer, a tubular body adapted to be detachably connected to a drill pipe, a pair of plates pivotally mounted in the lower portion of the body and adapted to swing outwardly therefrom, ;a piston arranged for reciprocatory movement within said tubular body, a piston rod dependingifrom said piston,

a substantially cylindrical crosshead on the lower portion of said piston rod, the upper corners of which plates are notched vertically and transversely forthe reception of the bushings on said crosshead and the lower portion of said piston rod andyco-operating means ons'aid plates and said body for limiting the outward swinging movement of said plates.

3. In an expansion bit and reamer, a tubular body, a pair of plates pivoted in the lower portion of said body, a rotary cutter journaled for operation in the lower portion of each plate, a

piston arranged for reciprocatory movement iii Within the tubular body, a tubular piston rod depending from said piston, a crosshead carried by the lower portion of said piston rod, which crosshead and the lower portion of which i piston rod are positioned in notches that are formed in the upper inner portions of said plates and a flow-bean removably positioned in the lower portion of said tubular piston rod.

4. In an expansion bit and reamer, a tubular body, a pair of plates pivoted in the lower portion of said body, a rotary cutter journaled for operation in the lower portion of each plate, a piston arranged for reciprocatory movement within the tubular body, a tubular piston rod depending from said piston, a crosshead carried by the lower portion of said piston rod, which crosshead and the lower portion of which piston rod are positioned in notches that are formed in the upper inner portions of said plates, a flow-bean removably positioned in the lower portion of said tubular piston rod and the lower portion of said tubular'body to the sides of the pivoted plate being provided with longitudinal disposed channels that receive and are traversed by the ends of the crosshead on said piston rod.

5. In an expansion bit and reamer, a tubular body, a pair of plates pivoted in the lower portion of said body, a rotary cutter journaled for operation in the lower portion of each plate, a piston arranged for reciprocatory movement within the tubular body, a tubular piston rod depending from said piston, a crosshead carried by the lower portion of said piston rod, which crosshead is positioned between the upper inner portions of said plates, a flow-bean removably positioned in the lower portion of said tubular piston rod and cooperating means on the crosshead and tubular body for guiding the movement of the crosshead longitudinally in said body.

6. In an expansion bit and reamer, a tubular body adapted to be detachably connected to a drill pipe, the lower portion of said body being provided with a transverse slot, plates pivoted to said body and occupying the end portions of the slot therein, a rotary cutter journaled for rotation on the lower portion of each plate, cooperating means on said plates and said body for limiting the outward swinging movement of said plates, a piston arranged for operation within the tubular body, a tubular piston rod dein claim 6 with spaced arms depending from said tubular body and a guide carried by the lower ends of said arms.

In an expanding bit and reamer, a tubular body provided in its lower portion with a transverse slot, pins rigidly seated in said body and extending across the slot therein, plates mounted for swinging movement on said pins, fluid pressure actuated means mounted for operation within said body for swinging said plates upon said pins, the lower outer portion of each plate being provided with an opening, a rotary cutter journaled for rotation on each plate and positioned in the opening'therein and a separately formed block rigidly secured to each plate for covering the outer portion of the opening therein and the outer face'of said rotary cutter.

10. In an expanding bit and reamer, a tubular body provided in its lower portion with a transverse opening, plates mounted for swinging movement in the end portions of said opening, fluid pressure actuated means for swinging said plates outwardly from the ends of said opening, pins seated in the lower portions of said plates, rotary cutters mounted for operation on said pins and separately formed blocks rigidly secured to the outer portions of said plates for covering the I outer faces of said rotary cutters.

11. In an expandingbit and reamer, a tubular body, a pair of plates pivotallymounted in the lower portion of said body and adapted to swing outwardly therefrom, fluid pressure actuated means arranged for operation within said tubular body for engaging said plates and swinging the same outwardly and means comprising trunnions on said crosshead and vertically disposed grooveswithin the lower portion of the tubular body for guiding the lower portion of said fluid pressure actuated means longitudinally of said body.

12. An expanding bit and reamer, as set forth in claim 11, with the upper inner portions of said plates being notched vertically and transversely for the accommodation of the lower portion of said fluid pressure actuated means.

13. An expanding bit and reamer, as set forth in claim 11 and with cooperating means on the upper portions of said plates and the adjacent portions of said body for limiting the outward and inward swinging movement of said plates.

14. In an expanding bit and reamer, a tubular body, fluid pressure actuated means arranged for operation within saidv body, a crosshead on the lower end of said fluid pressure actuated means, a pair of cutter carrying members mounted for swinging movement in the lower portion of said body and the upper inner portions of which plates are notched vertically for the reception of the lower portion of said fluid pressure actuated means and notched horizontally for the reception of said crosshead.

15. In an expanding bit and reamer, a tubular body, fluid pressure actuated means arranged for operation within said body, a crosshead, on the lower end of said fluid pressure actuated means, a pair of cuttercarrying members mounted. for

said plates and body for limiting the swinging movement of said plates in both directions.

DANIEL J. OGRADY. 

